Acidity and charge - AQA A Level Chemistry

I am quite confused by this... What is the difference between this:
e.g. M3+ e.g. Al3+ - more acidic in water than M2+ because greater charge : size ratio

and

Mg(OH)2 being slightly soluble in water as it lattice is stronger so fewer free OH- ions are produced - so lower pH (i don't even get where the free oh- ions come from)

I don't really understand what any of that means plus what polarising means, plus how a greater charge density makes it more acidic...

Sorry. This is confusing... but this is literally how my brain is right now.
please unconfuse me.

Thaanks

I am quite confused by this... What is the difference between this:
e.g. M3+ e.g. Al3+ - more acidic in water than M2+ because greater charge : size ratio

and

Mg(OH)2 being slightly soluble in water as it lattice is stronger so fewer free OH- ions are produced - so lower pH (i don't even get where the free oh- ions come from)

I don't really understand what any of that means plus what polarising means, plus how a greater charge density makes it more acidic...

Sorry. This is confusing... but this is literally how my brain is right now.
please unconfuse me.

Thaanks

I am quite confused by this... What is the difference between this:
e.g. M3+ e.g. Al3+ - more acidic in water than M2+ because greater charge : size ratio

and

Mg(OH)2 being slightly soluble in water as it lattice is stronger so fewer free OH- ions are produced - so lower pH (i don't even get where the free oh- ions come from)

I don't really understand what any of that means plus what polarising means, plus how a greater charge density makes it more acidic...

Sorry. This is confusing... but this is literally how my brain is right now.
please unconfuse me.

Thaanks

A metal with a 3+ charge is a stronger acid than a metal with a 2+ charge.
As the charge on the 3+ is greater, it attracts electrons from oxygen better than the metal with the 2+ charge. Therefore, this weakens the O-H bond and is more likely to be broken. It is easier to understand if you draw this out!

Right, i am not amazing at chemistry but i do know some of the answers...

a polar molecule - is one with charge, so if the overall molecule has a charge... it is a polar molecule... this also ties in with electronegativity

oh- ions come from either an alkaline solution or a water solution, in this case you are assessing the solubility in water.

by polarising a molecule... you are adding a charge to it

hope that helps

Thanks! I get the whole 3+ vs 2+ but i stil don't get why Mg(OH)2 has a lower pH than NaOH?

Thanks! I get the whole 3+ vs 2+ but i stil don't get why Mg(OH)2 has a lower pH than NaOH?